Southwest University of Science and Technology

About: Southwest University of Science and Technology is a education organization based out in Mianyang, China. It is known for research contribution in the topics: Adsorption & Graphene. The organization has 10017 authors who have published 8923 publications receiving 94850 citations. The organization is also known as: Xīnán Kējìdàxué.

Synthesis of one-molecule-thick single-crystalline nanosheets of energetic material for high-sensitive force sensor

Abstract: Energetic material is a reactive substance that contains a great amount of potential energy, which is extremely sensitive to external stimuli like force. In this work, one-molecule-thick single-crystalline nanosheets of energetic material were synthesized. Very small force applied on the nanosheet proves to lead to the rotation of the tilted nitro groups and subsequently change of current of the nanosheet. We apply this principle to design high-sensitive force sensor. A theoretical model of force-current dependence was established based on the nanosheets' molecular packing structure model that was well supported with the high resolution XPS, AFM analysis results. An ultra-low-force with range of several picoNewton to several nanoNewton can be measured by determination of corresponding current value.

Triple plasmon-induced transparency and optical switch desensitized to polarized light based on a mono-layer metamaterial.

Abstract: A mono-layer metamaterial comprising four graphene-strips and one graphene-square-ring is proposed herein to realize triple plasmon-induced transparency (PIT). Theoretical results based on the coupled mode theory (CMT) are in agreement with the simulation results obtained using the finite-difference time-domain (FDTD). An optical switch is investigated based on the characteristics of graphene dynamic modulation, with modulation degrees of the amplitude of 90.1%, 80.1%, 94.5%, and 84.7% corresponding to 1.905 THz, 2.455 THz, 3.131 THz, and 4.923 THz, respectively. Moreover, the proposed metamaterial is insensitive to the change in the angle of polarized light, for which the triple-PIT is equivalent in the cases of both x- and y-polarized light. The optical switch based on the proposed structure is effective not only for the linearly polarized light in different directions but also for left circularly polarized and right circularly polarized light. As such, this work provides insight into the design of optoelectronic devices based on the polarization characteristics of the incident light field on the optical switch and PIT.

Steady–shear‐induced Isothermal Crystallization of Poly(L‐lactide) (PLLA)

Abstract: The isothermal crystallization of poly(L‐lactide) (PLLA) under steady‐shear flow was investigated in situ using an optical polarizing microscope with a hot shear stage. The steady–shear‐induced crystalline morphology of PLLA, to a great degree, depends on the crystallization temperature. There is a critical temperature, 120°C, below which shear‐induced row nuclei enhance nucleation ability, leading to the improvement of crystallinity, and above which cylindrite structure is generated. Their numbers increase and size reduces with temperature owing to the better movement and relaxation behavior of chains in the presence of shear flow. The results of 2D wide‐angle x‐ray diffraction (WAXD), showing the oriented structure at high T c , and differential scanning calorimetry (DSC), detecting the rising of T m with increasing T c , well confirm the effect of T c on the crystallization of PLLA under shear flow.

Precisely Tuning Photothermal and Photodynamic Effects of Polymeric Nanoparticles by Controlled Copolymerization

Abstract: Cancer possesses normoxic and hypoxia microenvironments with different levels of oxygen, needing different efficacies of photothermal and photodynamic therapies. It is important to precisely tune the photothermal and photodynamic effects of phototherapy nano-agents for efficient cancer treatment. Now, a series of copolymeric nanoparticles (PPy-Te NPs) were synthesized in situ by controlled oxidative copolymerization with different ratios of pyrrole to tellurophene by FeCl3 . The photothermal and photodynamic effects of semiconducting nano-agents under the first near-infrared (NIR) irradiation were precisely and systematically tuned upon simply varying the molar ratio of the pyrrole to tellurophene. The PPy-Te NPs were used for cancer treatment in mice, exhibiting excellent biocompatibility and therapeutic effect. This work presents a simple method to tune photothermal and photodynamic therapies effect in semiconducting nano-agents for cancer treatment.